Respuesta :

Horizontal lines have the slope of 0. 
Y is the y intercept and B is the y coordinate of the Y intercept.  
debbieperez2002
since B is a constant, when used in a equation, y = b would mean that the "y" value will always be the same, and since it's always the same, it will be straight forever. Since Y is how high it is, since it's gonna stay the same that means it will be a horizontal line of the same height.